Resources
Feb 24, 2023

Grading A Diamond: The Four C's

Diamonds Above uses the Gemological Institute of America, or GIA, model for grading diamonds and determining their value. The model uses the four Cs, color, clarity, cut, and carat weight. GIA is the strictest diamond grading lab in the world and produces consistent results when compared to other labs. It is important to note that other labs use a variety of grading methods that do not produce consistent diamond grades, and are therefor inferior. Below is an small explanation of the diamond grading system and the four Cs. If you have any questions we would love to answer them and explain everything in detail, so give us a call or stop by Austin's premier diamond and gemstone jewelry store today!

Diamond Color Grades

One of the most visible qualities, and often times the most important, is a diamond's color. The diamond color evaluation of most gem-quality diamonds is based on the absence of color. A chemically pure and structurally perfect diamond has no hue, like a drop of pure water, and consequently, a higher value. GIA's D-to-Z diamond color-grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to stones of established color value.

GIA's diamond D-to-Z color-grading scale is the industry's most widely accepted grading system. The scale begins with the letter D, representing colorless, and continues, with increasing presence of color, to the letter Z. Many of these color distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price.

Diamond color is all about what you can’t see. Diamonds are valued by how closely they approach colorlessness – the less color, the higher their value. (The exception to this is fancy color diamonds, such as pinks and blues, which lie outside this color range.) Most diamonds found in jewelry stores run from colorless to near-colorless, with slight hints of yellow or brown. Less color equals more diamond sparkle!

Many of these color distinctions are so subtle as to be invisible to the untrained eye. But these slight differences make a very big difference in diamond quality and price. Seeking professional advice can ensure you buy a diamond that suits your tastes.

Diamond Clarity

Natural diamonds are the result of carbon exposed to tremendous heat and pressure deep in the earth. This process can result in a variety of internal characteristics called inclusions and external characteristics called blemishes. Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher its value.

  • Flawless(FL): No inclusions or blemishes are visible to a skilled grader using 10x magnification.
  • Internally Flawless(IF): No inclusions, only blemishes are visible to a skilled grader using 10x magnification.
  • Very, Very Slightly Included(VVS1 or VVS2): Inclusions are difficult for a skilled grader to see under 10x magnification. In each, the inclusions are invisible to the eye, appearing identical to the higher grades unless viewed under 10x magnification by a skilled grader.
  • Very Slightly Included(VS1 or VS2): Inclusions are not visible to the naked eye. Perhaps 1 in 100 untrained observers can detect VS2 inclusions with the naked eye, on close inspection under ideal conditions.
  • Slightly Included(SI1 or SI2): SI1 is the lowest grade with flaws often invisible to the naked eye. SI2 inclusions are usually visible to the naked eye, although they will require close inspection.
  • Included(I1): I1 diamonds have inclusions that are almost always visible to the naked eye.

Diamond Cut Styles and Cut Grades

Ideal Cut

This cut is intended to maximize brilliance, and the typically smaller table sizes of these diamonds have the added benefit of creating a great deal of dispersion or 'fire' as well. Ideal quality diamonds are truly for the person who enjoys knowing that he has one of the finest things that money can buy. This category applies only to round diamonds.

Excellent

In the case of round diamonds, many Excellent Cut diamonds have cuts that are the equal of any Ideal Cut diamond, though they often can be purchased at slightly lower prices than AGS Ideal Cuts. They are intended to provide maximum brilliance and fire. Like the Ideal Cut, these are also for the person who enjoys knowing that he has one of the finest things that money can buy.

Very Good

These diamonds reflect most of the light that enters them, creating a good deal of brilliance. With these diamonds, the cutters have chosen to stray slightly from the preferred diamond proportions in order to create a larger diamond. The result is that these diamonds fall slightly outside of some customers' preferences in terms of, for example, table size or girdle width, though, in many cases many of the parameters of diamonds in this range will overlap with certain parameters of diamonds in the Ideal or Excellent ranges. Generally, the price of these diamonds in slightly below that of Excellent cuts.

Good

Diamonds that reflect much of the light that enters them. Their proportions fall outside of the preferred range because the cutter has chosen to create the largest possible diamond from the original rough crystal, rather than cutting extra weight off to create a smaller Excellent quality diamond. Diamonds in this range offer an excellent cost-savings to customers who want to stay in a budget without sacrificing quality or beauty.

Fair & Poor

A diamond graded as fair or poor reflects only a small proportion of the light that enters it. Typically these diamonds have been cut to maximize the carat weight over most other considerations.

Diamond Carat Weight

All else being equal, diamond price increases with diamond carat weight, because larger diamonds are more rare and more desirable. But two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond. It's important to remember that a diamond's value is determined using all of the 4Cs, not just carat weight.

Diamond carat weight is the measurement of how much a diamond weighs. A metric "carat" is defined as 200 milligrams.

Complete the form & get a response from us soon!

Thank you! Your submission has been received!
Oops! Something went wrong while submitting the form.